BELLOWS-SHAPE CONTAINER

Abstract: A bellows-shape container with an integral circumferential wall comprising an opening positioned at the upper end, an upper shoulder portion adjacent to said opening, a lower bottom portion, a projection provided in such a manner as to project outwardly or inwardly of said lower bottom portion and at least one expanded portion that can be expanded and/or contracted, wherein when said bellows-shape container is contracted to the maximum, both the projection and the lower bottom portion are turned over, only the lower bottom portion is turned over with the projection remaining as it is, or either or both of the upper shoulder portion and the lower bottom portion are turned over so as to be loosely inserted into a dead space to thereby leave no dead space, and wherein a discharge nozzle, a discharge gun, an outlet pump and a discharge mechanism can be directly mounted on said container or an apparatus, an instrument or a discharge device equipped with said members can be mounted on said container so as to provide a number of functions.

Description: This invention generally relates to a plastics bellows container that can freely contract substantially along its longitudinal axis as the container's contents are expelled. More particularly, this invention relates to a plastics bellows container that can be easily and fully charged with highly-viscous fluid or pasty substances, and can discharge its contents substantially to its last drop. The plastics bellows container of the present invention may be connected to discharging means, such as a nozzle, gun, or pump, to discharge its contents conveniently. Plastics bellows containers are widely used chiefly as disposable containers for pasty substances, as most plastics bellows containers can be manufactured at very low cost. Conventional plastics bellows containers generally have many bellows provided longitudinally along their side wall portions, which contract and expand along their longitudinal axis like an accordion. Plastics bellows containers are conventionally manufactured conveniently by blow moulding. Though it is usually desirable to provide the same thickness to all portions of the containers, conventional blow moulding will not provide evenly-thickened walls of plastics bellows containers. The farther away a portion is from the longitudinal central axis, the thinner it is. Thus, the outer ridges of the bellows are much thinner than the inner ridges of the bellows, as the outer ridges are farther away from the central axis than the inner ridges. Thus, when a plastics bellows container is contracted, the axial piling of the "thick" inner portions of the bellows create a space or "dead-space" within the container about its longitudinal axis. Therefore, thick and pasty substances, such as grease or printing ink, left in such dead-space may not be discharged fully from the container, which is destined to be disposed of together with its contents, which is a waste of resources. A number of plastics bellows containers have been proposed in an attempt to discharge as much content in the 'dead-space' as possible, such as: (1) Japanese Utility Model laid-open Publication No. 4-7478 discloses a plastics bellows container with a raised bottom to eliminate dead-space; (2) Japanese Utility Model laid-open Publication No. 59-168 350 discloses a plastics bellows container also with an inward bottom protrusion shaped to eliminate not only dead-space but also the inside of the neck portion; (3) Japanese Utility Model laid-open Publication No. 59-174 474 discloses a plastics bellows container with a raised bottom, which is shaped to fit the otherwise formable dead-space; (4) Japanese Utility Model laid-open Publication No. 60-169 143 discloses a plastics bellows container with a raised bottom shaped to fill not only the dead-space but also the inside of the neck portion; and (5) Japanese Utility Model laid-open Publication No. 56-100 347 (1981) discloses a plastics bellows container with its bellows tapered along its side wall. The raised bottom of the plastics bellows container of document (1) is separately prepared and incorporated into the bellows container at its bottom in an additional manufacturing step. The thickness of the raised bottom may be made adequate, however, the production cost for such separately made bellows containers will be pushed up considerably, becoming considerably higher than the cost for manufacturing single-unit type plastics bellows containers. The plastics bellows containers of documents (2)-(4) can all be made substantially in a single blow-moulding step, however, their dead-spaces are not eliminated. If their dead-space elimination means or protrusions on the bottom are to be made rigid enough, the inner ridge portions of their bellows are destined to also become 'too-rigid', not only inconveniencing use of such bellows containers but also resulting in creation of large dead-spaces within those containers. If the inner ridge portions of the bellows are to be made conveniently thin to eliminate formation of dead-space as much as possible, their protrusions are then destined to become too thin (soft) and cannot function as expected. It has not been practically possible so far with such known bellows containers to eliminate dead-space with such dead-space elimination means. Further, the raised bottoms of the plastics bellows containers of documents (1)-(4) unavoidably make the utilisable space that much smaller. In addition, those raised bottoms will hinder filling up of the remaining portions of those plastics bellows containers with highly pasty substances, since the air entrapped in the narrow corner portions between such raised bottoms and the side walls of those bellows containers will remain entrapped in the containers during their filling operation. In order wholly to eliminate such shortcomings of those plastics bellows containers, use of very-complicated mould means is required. Plastics bellows containers produced with very-complicated mould means will become considerably expensive, which is a serious drawback to dispensable types of plastics containers. The plastic bellows container (5) provides an improvement in that it will not have large dead-space when the bellows container is fully contracted, however, it cannot totally eliminate dead-space, either. Although all the plastics bellows containers (1)-(5) can provide a considerable improvement in elimination of dead-space, none of them can substantially and effectively eliminate dead-space. This same objection applies to the container disclosed in US-A-5 333 761, which is rendered collapsible by utilising pairs of walls which are of chevron cross-section. When the container is partially collapsed to discharge some of its contents, the angle between each pair of walls is reduced. This reduction is resisted by the resilience of the material from which the container is made, which continually tries to restore this angle to its original value. This leads to the container's tending to increase its volume when released, causing it to suck air in. This is in contrast with the containers of this invention, which tend to stay in their collapsed positions. Accordingly, it is an object of the present invention to provide a plastics bellows container which can discharge very pasty substances such as very pasty foods, cosmetics, detergents, ointments, chemicals and oils practically to their last drop. When airtight means is provided to the container, the container can keep its contents from contacting the atmosphere and bacteria so that oxidation or degradation of the contents may be avoided. It is another object of the invention to provide such improved plastics bellows containers economically. It is still another object of the invention to provide such containers with various novel configurations while retaining the foregoing features, which has not be possible with known containers. The containers of this invention may be attached to discharge means, such as a nozzle, gun or pump. The plastics bellows containers of the present invention can be produced of a plastics material in a conventional manner. The bellows containers according to the present invention may be conventionally manufactured by direct blow moulding, protrusion blow moulding, injection blow moulding, etc., which are all well known. A bellows container according to the present invention comprises a neck portion, several bellows sections each having a first wall (A) and a second wall (B), and a base. The walls (A) and (B) fully contact each other respectively when fully contracted, and create practically no space or gap therebetween. In some embodiments, the inner ridge portions of the side bellows are not vertically aligned, so that, when fully contracted, the inner ridges of the bellows do not create much void within the containers. Bellows containers can be made in varied configurations according to the present invention. In all cases, the walls (A) and (B) of the bellows can substantially fully contact each other respectively. The unique configuration feature of the walls (A) and (B) retains the portions contacted. One embodiment of the bellows container of the present invention has a generally-cylindrical shape. A preferred bellows container is made generally like a truncated cone or reverse truncated cone having a bottom protrusion, such that the inner ridges of the bellows are not axially aligned. The bottom protrusion can be pushed into the container. The bellows containers according to the present invention may be appropriately attached to stop valves or airtight valves which can prevent the content from flowing back into the containers. The bellows containers according to the present invention may be provided with desired discharging means such as a discharge nozzle, discharge gun, or discharge pump. An air-tight type of bellows container of the present invention can keep the content without contacting the air for the container can remain contracted progressively as the content is discharged. All the bellows containers of the present invention can eject almost all their content, and they can be manufactured economically. The present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1(a) is a view, part in section and part in elevation, of one embodiment of the present invention in its maximum-volume condition; Figure 1(b) is a similar view of the Fig. 1 embodiment in its fully-contracted condition; Figures 2(a) and (b) are views similar to Fig. 1 of another embodiment; Figures 3(a) and (b) are views similar to Fig. 1 of another embodiment; Figures 4(a) and (b) are views similar to Fig. 1 of another embodiment; Figures 5(a) and (b) are views similar to Fig. 1 of another embodiment. The plastics bellows containers of the present invention can be made economically enough to be disposable in a single process by blow moulding means. Figs. 1(a) and (b) show an embodiment of the bellows container 60 of this invention. In this embodiment, the bellows 65 of the container 60 are axially aligned, therefore the container 60 will have rather a large void inside it when the container is fully contracted. The void (dead-space) will be virtually eliminated when the top shoulder portion 62 is reversed and pressed into the inside of the container 60 together with the neck portion 61. In the embodiment as well, all the contents of the container save that left in the neck portion 61 will be pushed out of the container 60 effectively. Another embodiment of the bellows container of this invention is shown in Figs. 2(a) and (b), which is a modification of the bellows container 60 of Figs. 1. The bellows container 60' has its bellows 65 axially in off-alignment so that when the container 60' is fully contracted, the void inside is smaller or shallower than that in the bellows container 60. The smaller void is eliminated as described for the bellows container 60. Figs. 3(a) and (b) show another embodiment bellows container 70 which is a modified version of the bellows container 60 of Figs. 1(a) and (b). The bellows container 70 has a bottom shoulder portion 73 instead of a top shoulder portion 62. The bottom shoulder portion 73 when reversed eliminates the void inside the container 70. All the contents save the contents left in the neck portion 71 will be pushed out effectively. The bellows container 70' shown in Figs. 4(a) and (b) is a modified version of the bellows container 60', where the bellows are arranged such that the upper bellows (as viewed) are smaller across than the lower bellows. The bellows container 70' has a bottom shoulder portion 73 instead of a top shoulder portion 62. All the contents except those left in the neck portion 71 will be effectively pushed out when the bellows container 70' is fully contracted. Figs.5(a) and (b) show another embodiment of the container of this invention. The bellows container 80' comprises three bellows units. The top unit has three bellows each different in size, the middle unit has a single bellows which is the smallest of all the bellows, and the bottom unit has three bellows each different in size. The top shoulder portion 82 and the bottom shoulder portion 83, when reversed, eliminate the void inside the container cooperatively. All the contents except those left in the neck portion 81 may be expelled when the container is moved to its contracted condition. Plastics bellows containers can be made with various cross-sections, such as a triangle, rectangle, pentagon, hexagon, octagon or dodecagon. The walls (A) and (B) of each bellows unit of this invention may take other shapes as long as they can contact each other respectively, leaving no void therebetween, and stay contacted when the bellows container is fully contracted. Although most above embodiments show otherwise, the walls (A) may approach and contact the walls (B) after they have become introverted. It does not matter which wall stays largely in its original shape, and which wall becomes introverted. What matters is that after the walls come into contact with each other, they stay in the contacting position even when the force moving the container into its contracted condition is removed. It is advantageous to seal the opening or neck portion of the bellows containers of the present invention to prevent leakage of the content and entry of bacteria. Such sealing means (not shown) can be of metal, paper or resin, and can be incorporated in the bellows container conventionally. It is also advantageous to provide the bellows containers of the present invention with valve means (not shown) to prevent reverse flow of the contents to prevent the entry of air, so that the contents can be kept fresh. Such valve means may be provided on the bellows containers conventionally. It may be advantageous to attach nozzle means (not shown), such as a flower-shaped or star-shaped nozzle, to the neck portion to extrude a pasty content, such as mayonnaise, in a flower or star shape. In addition, it will be convenient to utilise extrusion means or discharge means such as a spray gun (not shown) or airless pump (not shown). Bellows containers having such discharge means can remain in their intermediate contracted positions as the contents are progressively expelled. In all the embodiments described above, the plastics bellows containers according to the present invention are capable of discharging practically all the contents. Materials from which the containers of the present invention can be made include thermoplastic materials, such as polyethylene, polypropylene, polyvinyl chloride and polyester, and bio-degradable plastics materials, such as fatty acid polyester, polyglycol acid and polylactic acid, or photo-degradable plastics materials. In other words, the bellows containers of the present invention can be manufactured from conventional plastics materials in conventional manners. The portions farther away from the central axis of the containers of the present invention will be made thinner than the portions nearer to the central axis, as in the case of conventional plastics bellows containers. However, the bellows containers according to the present invention will still retain such advantageous features as described above, while conventional bellows containers cannot.

Claims: A contractile container (60, 60',70, 70', 80, 80') of plastics material, comprising: at least one bellows unit (65, 65', 75, 75', 85, 85') in the form of a pair of walls (A, B); a neck portion (61, 71, 81) extending from one of the end walls (A) of the container and having in it a port for the passage of liquids or pastes out of the container, the walls of each pair being movable about their common boundaries between a maximum-volume position and a minimum-volume position, characterised in that the two walls (A, B) of each pair are part-spherical and form a bistable combination; one of the walls of each pair, when the pair moves from its maximum-volume position to its minimum-volume, stable, position, becomes introverted, so that the inner surfaces of the walls come into contact with each other and are of a complementary curvature, whereby there is virtually no dead-space between the contacting walls, and the central section of the end wall (A) having the neck portion also has a contiguous outer dished section (62, 82) which, when in its minimum-volume position, adopts a shape which is complementary to the shape of the envelope of the inner boundaries of at least some of the walls intermediate the end walls when the said intermediate walls are in their minimum-volume positions. A container as claimed in claim 1, comprising a plurality of bellows units having their inner peripheries joined together to form a longitudinal bellows of annular cross-section. A container as claimed in claim 2, in which the bellows is of generally-cylindrical shape. A container as claimed in claim 2, in which the bellows is of generally-tapering shape. A container as claimed in any preceding claim, in which the end wall (B) of the bellows unit which is most remote from the neck portion has an integral central dished section (73, 83) which is introvertible between a maximum-volume position and a minimum-volume position relative to the wall. A container as claimed in claim 5, in which at least a part of the dished central section, when in its minimum-volume position, adopts a curvature which is complementary to the curvature of the end wall (A) from which the neck portion projects. A container as claimed in claim 6, in which the end wall (B) which is most remote from the neck portion has a contiguous section (53, 73, 83) which, when in its minimum-volume position, adopts a shape which is complementary to the shape of the envelope of the inner boundaries of at least some of the said intermediate walls when in their minimum-volume positions.

Inventors: MAZDA MASAYOSI, MAZDA, MASAYOSI
Applicants: MAZDA MASAYOSI, MAZDA, MASAYOSI
Application year: 1994
Main classification: B65D21
IPC codes: B65D1, B65D35, B65D83, B65D21